SQL Server Losing Connections

We have Dynamics AX vm servers, BizTalk servers all dropping connections to SQL Server. SQL never seems to go down. The client applications crash for a minute. All Terminal services start 'reconnecting', but I see event error logs on the Dynamics AX and BizTalk servers saying there's a problem connecting to SQL Server. I don't see any errors on the SQL side.

Any help on trouble shooting this? I've been here for like 7 hours trying to figure this out.

Hey brett, lets assume that the network admin is doing his own thing, how can I prove that it's the switch?

I'm running the Microsoft Network Monitor 3.4, and I'm filtering on Property.TCPRetransmit == 1 which seems to find an ip that would be our SAN Controller HBA. We only have the tempdbs on the SAN, but maybe that's the issue?

Go into the SQL Server Configuration Manager and look at the Protocols that
are there and what is enabled.

The way Named Pipes works is that it goes to a DC and then the DC gives it
a token and connects it to the SQL Server. If that DC loses connectivity or
goes down the client can no longer talk on that link and has to reestablish
a brand new connection.

With TCP/IP the client connects to the SQL Server and then SQL broadcasts
an authorization request. Any DC can give the token and then it works from
there. If the client/SQL needs a new authentication, TCP just broadcasts
for a new token.